1. Field of the Invention
Embodiments of the invention relate to the field of fire alarm systems.
2. Discussion of Related Art
In current technology, firefighter telephone systems that are deployed in structures such as multi-story buildings employ multiple fixed communication installations that typically include a pre-mounted telephone handset, or a receptacle into which a portable handset can be connected in order to communicate with other points in the telephone system. By providing multiple fixed communication installations for telephone equipment, a firefighter is afforded the ability to communicate with other firefighters or with a command station. However, the fixed communication installations tether a firefighter to the particular location which may hamper work during an emergency. For example, the firefighter may have limited access to the location of a fixed communication installation due to an emergency condition within a building, or may be required to travel to a location of the fixed communication installation that hampers the ability to respond to the emergency and to assess the situation in another part of the building where an emergency condition exists.
In order to provide firefighters with greater flexibility, some town and/or city agencies provide radio equipment including radio repeaters with fire department vehicles to facilitate communications. High power radios (˜40 W) may also be provided for use by firefighters when entering a building in response to a call. This facilitates the ability of the firefighter to communicate with a command station from within the interior of the building. However, such high power radios are bulky, heavy and emit radio signals that may still be of insufficient strength to penetrate interior parts of a building, such that communications may still be degraded or cut-off within certain structures.
In other approaches, buildings may install emergency equipment for radio communications that use radiating cable (“leaky coax”) in order to facilitate firefighter communications. However, the radio strength leaked from floor to floor in a building employing leaky coax may generally be less than that employed in active radio systems. Moreover, because wiring in such systems is unsupervised, an accidental cut in a coaxial cable would unlikely be identified until radio communications are attempted and result in failure. This event may occur during an actual emergency in which case the radio communications failure may have severe consequences.